Cotton picker doffer



Jan. 25, 1955 WALKER 2,700,266

COTTON PICKER DOFFER Filed July 16, 1953 nvvrm 05105 A. WALKER ATTORNEY United States Patent COTTON PICKER DOFFER Delos A. Walker, Memphis, Tenn., assignor to Inter- ;iational Harvester Company, a corporation of New ersey Application July 16, 1953, Serial No. 368,318

8 Claims. (Cl. 56-41) This invention pertains to dofiers for removing cotton from the picker spindles of cotton picking machines and more particularly concerns improvements in the doffer-disk assembly.

A dofier assembly of the general character as that embodying the present invention, together with environment for such assembly, is disclosed in U. S. Patent 2,247,682. The dofler assembly shown in said patent comprises a metal disk having an annulus of rubberlike material secured to a face thereof by clamping elements. The rubber annulus includes a plurality of luglike doffing pads projecting therefrom axially of the disk and spaced apart circumferentially thereof. These doffing pads are also rubber and formed integrally with the rubber annulus, the lugs being pliable and resilient to facilitate their wiping engagement with the picker machine spindles to strip the cotton therefrom without injuring said spindles. To assure firm bonding of the rubber annulus upon the metal disk, such disk has been provided with projections respectively registering with the back sides of the dofiing pads and projecting into nesting relation with cavities therein. Because of these metal projections into the pads, they reduce the flexibility of the lugs as well as the rubber content of these lugs so that the material is subjected to high-stress loading which fatigues the material and accelerates its deterioration.

An important object of this invention is the provision of a noval doifer assembly wherein the doffing lugs are formed on an annulus which with the lugs is formed of rubber-like material and wherein the dofling lugs and annulus are secured to the mounting plate or support in such manner as to enhance the resiliency of the dotting lugs and the mounting thereof to the support.

A further object of this invention is the provision of a novel support disk which provides a plurality of radially outwardly extending fingers separated circumferentially from each other, the fingers being connected to the annulus with the lugs disposed in axial registry with the fingers.

The invention also comprehends the provision of a disk with axially flexible fingers so that the lugs are individually axially movable.

These and other objects of the invention will become more apparent from the specification and the drawing, wherein:

Figure 1 is a top plan view of the novel support disk;

Figure 2 is a bottom view of the disk with the dofiing means assembled therewith; and

Figure 3 is a radial sectional view taken substantially on the line 3-3 of Figure 2.

Describing the invention in detail, the doffer assembly, generally designated 2, comprises a disk-like carrier unit 3 formed symmetrically about a principal axis 4, seen as a point in Figure 1. The unit 3 may be formed of aluminum, although preferably it is made of flexible material, such as plastics or even steel. During the operation of the entire dofier assembly 2, it is caused to rotate about the axis 4.

The disk-like unit 3 has a central generally cylindrical hub 5 extending axially of the unit concentric with the axis 4, and the hub intermediate its ends is formed integral with the inner periphery of a circumscribing plate portion 6 ocncentric with the axis 4. The plate portion 6 is dished axially and provides a concave reverse side 7 and a convex obverse side 8. The outer periphery of the plate portion 6 is defined by an axially extending ring portion 9 which on its interior side 10 is 2,700,266 Patented Jan. 25, 1955 .10 and the periphery 12 of the hub, and along its.

longitudinal edge is integral with the side 7 of the plate portion 6. It will thus be noted that the center plate portion 6 is relatively axially rigid.

The outer periphery of the ring portion 9 is formed with a plurality of equally spaced radially outwardly extending fingers 13, 13 which are tapered at their lateral edges 13', 13' toward their outer extremities and define V-shaped slots .14, 14 therebetween with the apex of the V directed radially inwardly of the support unit 2. This provides fingers having greatest flexibility at their outer ends and progressively less flexibility inwardly of said ends. It will be noted from a consideration of Figure 2 that the ribs 11, 11 are disposed in radial alignment with alternate fingers 13 whereby the intermediate fingers are slightly more flexible. The fingers are flat and lie in a common plane substantially perpendicular to the axis 4.

An integral unit 15 of elastomer material comprises an annular wafer-like web 16 having an obverse face 17 and a reverse face 18, said reverse face being bonded or vulcanized to one side 19 of the fingers. The inner perimetric edge 20 of the web registers with the outer perimeter of the ring 9 and a circular flange 21 of the web 17 is formed about its outer periphery and extends along the outer perimetric edge thereof and projects axially of the plate from the reverse face of such web in contiguity with the outer edges 22 of the fingers and bonded or vulcanized thereto.

A plurality of doffing lugs or pads 23 project axially from the obverse face 17 of the elastomer unit 15 and these lugs are each disposed in axial registry with the respective fingers 13, 13 whereby there is a direct backing for each lug.

The elastomer unit 15 may be formed of natural rubber, synthetic rubber-like material, or a blend of these two materials. The material from which the unit 15 is made preferably or possesses characteristics of soft vulcanized rubber having a resistance to displacement and elasticity approximating that of tread projections on conventional automobile tires.

It will be noted that in the instant design, the unit 15 is bonded or connected to the fingers only and that is in axial registry with the lugs and that the web spans the spaces between the fingers and has a free flow action. This feature affords a yieldable resistance to the axial flexing of each finger and furthermore, also accommodates circumferential flexing of each lug principally in tension over an extensive length of the web in view of the unsupported nature thereof so that there actually is a stretching action of said web in lieu of a highly localized stress concentration on a small amount of rubber materiel which is immediately in axial contiguity with the lug. During axial flexing of the fingers, the tensile elasticity of the web portions between adjacent lugs is due to the relative axial displacement of the fingers.

What is claimed is: 1. A dofler assembly comprising a plate-like unit for rotation about a principal axis thereof, and having a plurality of circumferentially spaced radially outwardly extending fingers disposed within a plane substantially perpendicular to said axis; an integral unit of elastomer material comprising an annular wafer-like web having an obverse face and a reverse face and connected at said reverse face to said fingers, and a lug associated with each finger and integral with said web and projecting axially from said obverse face thereof and disposed in registry with the related finger.

2. A dotfer assembly according to claim 1 and said fingers having outer extremities and formed of flexible material for individual flexing axially of said unit and said fingers being most flexible at their outer extremities and progressively less flexible from said extremities toward said axis.

3. A dolfer assembly comprising a carrier for rotation about a principal axis thereof and including a plurality of radially outwardly extending fingers spaced circumferentially about said axis, and dofier means formed of clastomer material connected to said fingers and including an axially extending lug on each finger and said material extending between and interconnecting said fingers.

4. The combination according to claim 3 and said fingers tapered radially outwardly.

5. A doffer assembly comprising a carrier unit for rotation about a principal axis thereof and including a central plate-like portion, a series of circumferentially spaced fingers connected to said portion and projecting radially outwardly thereof, and a dofiing element of elastomer material having a wafer-like annular web substantially coaxial with said axis and having an obverse side connected to said fingers, said web having a reverse side with integral axially projecting lugs disposed in axial registry with respective fingers and said web interconnecting all of said fingers and extending radially substantiallythe full length of said fingers.

6. For a cotton picker doffer assembly, a plate-like element for rotation about a principal axis thereof comprising a plurality of doffer-pad sustaining radially outwardly extending circumferentially spaced fingers.

7. The combination according to claim 6 and said plate-like element comprising a "substantially rigid, circular center portion and said fingers spaced about the outer periphery thereof and connected therewith and flexible axially of said element.

8. The combination according to claim 7 and said fingers comprising fiat metallic members disposed in a single plane, and each finger having lateral edges converging radially outwardly and having a narrow outer end portion for increased flexibility and a broad inner portion for reduced flexibility and rigid connection to said center portion.

References Cited in the file of this patent UNITED STATES PATENTS 2,247,682 Hagen July 1, 1941 2,619,682 Paradise Dec. 2, 1952 2,654,202 Millard Oct. 6, 1953 2,654,203 Parkerton Oct. 6, 1953 

